Field of the Invention
A composite solid, or semi-solid state polymer electrolyte for electrochemical devices which is preferably comprised of two layers, with the first layer being a tough, mechanically strong adhesive layer that is non-reactive with alkali metals such as lithium, and the second layer being an adhesive layer containing aprotic liquids and alkali metal salts which migrate into the first layer, but do not destroy the first layer, and do not substantially react with alkali metals.